Basics: Guest Post 3: Sperm maturation and ejaculation

Mar 18 2010 Published by under Basic Science Posts

What you all were waiting for has finally come! Yeah.
Sperm maturation and ejaculation
OK!! So the last time I was over here at Neurotopia we were talking about sperm in their infancy. We discussed spermatogenesis -- how we got from a diploid spermatogonial stem cell to a haploid spermatid -- and then spermiogenesis -- the process by which the spermatids acquire the features of spermatozoa: tails, acrosomes and the like.
We stopped there when the sperm had just graduated from diapers to their big kid undies, and we'll pick up where we left off.

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Friday Weird Science: Ejaculation 1, 2, 3...

Mar 12 2010 Published by under Friday Weird Science

Well well well. Here we are. It's Friday. And we've been talking about SPERM ALL WEEK.
What to do...what to do... Nel-Themaat et al. "Quality and freezing qualities of first and second ejaculates collected from endangered Gulf Coast Native rams" Animal Reproduction Science, 2006.
So it turns out that the people who wrote the study Sci covered the other week wrote ANOTHER one. Also, it turns out the eland is not endangered, but the other species they were working with, the Gulf Coast Native Sheep, IS endangered. Though it's a rather odd beastie, in that it originally was from a population of European sheep brought over to the US, which escaped, went feral, and is now considered its own variety. This is an important sheep to look at in particular because the Gulf Coast Sheep has become adapted to living in a moist environment (as some of you may be aware, the southeast of the US is very moist, in some areas is it entirely IMPOSSIBLE to get all the mildew out of your house EVER), being less sensitive to parasites and less sensitive to fungal problems like foot rot. This means that if you wanted to, say, work with sheep in humid environments (sheep are often introduced domestically for very poor areas, and the southeastern US is apparently trying to reintroduce them. It is Sci's hope that they might eat the dang kudzu), you might want to take a look at these Gulf Coast sheep, and maybe steal of their useful genes for your benefit. And of course if you are going to steal some genes and breed some of these Gulf Coast sheep into your stock you need...some sperm.

Multiple ejaculates. Because once is never enough.
Oh and also:

For those who don't know about kudzu. It SUCKS. A lot. There's a house under there, under the lump in the middle. Really. It was introduced (I think from Japan) as something for cows and sheep and stuff to forage on. Also, it was apparently ornamental (*snort*). There was only one problem with the plant.
Cows WON'T EAT IT. I mean, they'll eat it if they're STARVING, but they don't enjoy it. Goats don't either. NO ONE DOES. And kuzdu can grow like...kudzu. In the southeast, it takes over EVERYTHING. Every spring and summer becomes a war on the kudzu. A sheep that would eat this crap would get a grateful hug from Sci every day of it's little life. It would also get VERY fat.
Anyway. Back to semen. I know what you guys REALLY want to hear about.

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Friday Weird Science: Sex Therapists and the Expectations

Feb 19 2010 Published by under Friday Weird Science

We hereby take a break from the female reproductive cycle to ask:
How's your sex life?
How do you FEEL about your sex life?

More importantly, how does your SEX THERAPIST feel about your sex life? Corty EW, Guardiani JM. "Canadian and American sex therapists' perceptions of normal and abnormal ejaculatory latencies: how long should intercourse last?" Journal of Sexual Medicine, 2008.

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Friday Weird Science: Creative Uses of the Stopwatch

Dec 11 2009 Published by under Friday Weird Science

For Sci, the weird science tends to come in spurts (heh heh...heh). There will be times when I am literally digging through Pubmed trying to find ANYTHING ODD AT ALL, and then there are times, like now, when people are tweeting and emailing and g-chatting and all but screaming in my ear with the weird. Got enough crazy sexual crap around here to last for WEEKS.
And a good thing, too, cause it's all about premature ejaculation, and don't we all wish we could last for weeks...
So we get to this week. I was going to cover an amazing dog caper, but this one is so very relevant to LAST week's weird science that I felt they had to follow in sequence. Dog capers next week. Stay tuned. Waldinger et al. "A multinational population survey of intravaginal ejaculation latency time." J. Sex. Med. 2005.
And I hereby dedicate this post (for better or worse...) to Miriam of the Oyster's Garter (and Seaplex!), who sent Sci the paper within TWO MINUTES of me sending out a desperate tweet for journal access. She was not a bit premature. 🙂 Also, yay Twitter.

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Friday Weird Science: Hyposexual, Hypersexual, and Oxytocin

Dec 04 2009 Published by under Friday Weird Science

Oh, you all thought oxytocin posts were DONE!? BY NO MEANS. For oxytocin lends itself to the truly weird science, and this one simply could not be ignored. In addition, Sci is compelled to blog this paper out of sympathy and understanding for the poor little grad student (or possibly the tech) who WITNESSED this entire experiment, on a weekly basis, for I don't know how long. Oh you devoted servant of science, Sci takes her hat off to you this day.
...moment of silence... Pattij, et al. "Individual differences in male rat ejaculatory behavior: searching for models to study ejaculation disorders." European Journal of Neuroscience, 2005.
We'll get to what the poor student did in a minute.
So what, might you think, is the biggest problem in sexual dysfunction these days? From the abundance of couples in matching bathtubs and various other really awful commercials for Cialis and Viagra, etc, you'd really think it was erectile dysfunction. But in fact, there is ANOTHER sexual disorder that is possibly more common, and which has just as big of an impact on a guy's sexual quality of life...
(Before you go below the fold, things possibly NSFW, blah de blah, it's Friday, you should know this by now.)

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Oxytocin: Let's hear it for the boys!

Nov 17 2009 Published by under Behavioral Neuro

Sci will be honest. The migraine continues apace. But the oxytocin, it must be blogged. And the migraine medication, it makes Sci loopy! Given what I'll be blogging today, that might not be a bad thing...

I've already gone through some of the basics of oxytocin, and the famous effects that oxytocin has on females. But what most general biology and physiology courses don't tell you is the big role that oxytocin plays in MALES. This molecule isn't just for the ladies.
Let's hear it for the boys:

(Nothing says manly men like high kicks)

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13 responses so far